rlm_counter.c

radius服务器

		return -1;
	}
	data->gdbm = gdbm_open(data->filename, sizeof(int),
			GDBM_WRCREAT | GDBM_COUNTER_OPTS, 0600, NULL);
	if (data->gdbm == NULL) {
		radlog(L_ERR, "rlm_counter: Failed to open file %s: %s",
				data->filename, strerror(errno));
		counter_detach(data);
		return -1;
	}
	if (gdbm_setopt(data->gdbm, GDBM_CACHESIZE, &cache_size, sizeof(int)) == -1)
		radlog(L_ERR, "rlm_counter: Failed to set cache size");

	/*
	 * Look for the DEFAULT1 entry. This entry if it exists contains the
	 * time of the next database reset. This time is set each time we reset
	 * the database. If next_reset < now then we reset the database.
	 * That way we can overcome the problem where radiusd is down during a database
	 * reset time. If we did not keep state information in the database then the reset
	 * would be extended and that would create problems.
	 *
	 * We also store the time of the last reset in the DEFAULT2 entry.
	 *
	 * If DEFAULT1 and DEFAULT2 do not exist (new database) we add them to the database
	 */

	key_datum.dptr = (char *)default1;
	key_datum.dsize = strlen(default1);

	time_datum = gdbm_fetch(data->gdbm, key_datum);
	if (time_datum.dptr != NULL){
		time_t next_reset = 0;

		memcpy(&next_reset, time_datum.dptr, sizeof(time_t));
		free(time_datum.dptr);
		if (next_reset && next_reset <= now){

			data->last_reset = now;
			ret = reset_db(data);
			if (ret != RLM_MODULE_OK){
				radlog(L_ERR, "rlm_counter: reset_db() failed");
				counter_detach(data);
				return -1;
			}
		}
		else
			data->reset_time = next_reset;
		key_datum.dptr = (char *)default2;
		key_datum.dsize = strlen(default2);

		time_datum = gdbm_fetch(data->gdbm, key_datum);
		if (time_datum.dptr != NULL){
			memcpy(&data->last_reset, time_datum.dptr, sizeof(time_t));
			free(time_datum.dptr);
		}
	}
	else{
		ret = add_defaults(data);
		if (ret != RLM_MODULE_OK){
			radlog(L_ERR, "rlm_counter: add_defaults() failed");
			counter_detach(data);
			return -1;
		}
	}


	/*
	 *	Register the counter comparison operation.
	 */
	paircompare_register(data->dict_attr, 0, counter_cmp, data);

	/*
	 * Init the mutex
	 */
	pthread_mutex_init(&data->mutex, NULL);

	*instance = data;

	return 0;
}

/*
 *	Write accounting information to this modules database.
 */
static int counter_accounting(void *instance, REQUEST *request)
{
	rlm_counter_t *data = (rlm_counter_t *)instance;
	datum key_datum;
	datum count_datum;
	VALUE_PAIR *key_vp, *count_vp, *proto_vp, *uniqueid_vp;
	rad_counter counter;
	int rcode;
	int acctstatustype = 0;
	time_t diff;

	if ((key_vp = pairfind(request->packet->vps, PW_ACCT_STATUS_TYPE)) != NULL)
		acctstatustype = key_vp->lvalue;
	else {
		DEBUG("rlm_counter: Could not find account status type in packet.");
		return RLM_MODULE_NOOP;
	}
	if (acctstatustype != PW_STATUS_STOP){
		DEBUG("rlm_counter: We only run on Accounting-Stop packets.");
		return RLM_MODULE_NOOP;
	}
	uniqueid_vp = pairfind(request->packet->vps, PW_ACCT_UNIQUE_SESSION_ID);
	if (uniqueid_vp != NULL)
		DEBUG("rlm_counter: Packet Unique ID = '%s'",uniqueid_vp->strvalue);

	/*
	 *	Before doing anything else, see if we have to reset
	 *	the counters.
	 */
	if (data->reset_time && (data->reset_time <= request->timestamp)) {
		int ret;

		DEBUG("rlm_counter: Time to reset the database.");
		data->last_reset = data->reset_time;
		find_next_reset(data,request->timestamp);
		pthread_mutex_lock(&data->mutex);
		ret = reset_db(data);
		pthread_mutex_unlock(&data->mutex);
		if (ret != RLM_MODULE_OK)
			return ret;
	}
	/*
	 * Check if we need to watch out for a specific service-type. If yes then check it
	 */
	if (data->service_type != NULL) {
		if ((proto_vp = pairfind(request->packet->vps, PW_SERVICE_TYPE)) == NULL){
			DEBUG("rlm_counter: Could not find Service-Type attribute in the request. Returning NOOP.");
			return RLM_MODULE_NOOP;
		}
		if ((unsigned)proto_vp->lvalue != data->service_val){
			DEBUG("rlm_counter: This Service-Type is not allowed. Returning NOOP.");
			return RLM_MODULE_NOOP;
		}
	}
	/*
	 * Check if request->timestamp - {Acct-Delay-Time} < last_reset
	 * If yes reject the packet since it is very old
	 */
	key_vp = pairfind(request->packet->vps, PW_ACCT_DELAY_TIME);
	if (key_vp != NULL){
		if (key_vp->lvalue != 0 &&
		    (request->timestamp - key_vp->lvalue) < data->last_reset){
			DEBUG("rlm_counter: This packet is too old. Returning NOOP.");
			return RLM_MODULE_NOOP;
		}
	}



	/*
	 *	Look for the key.  User-Name is special.  It means
	 *	The REAL username, after stripping.
	 */
	key_vp = (data->key_attr == PW_USER_NAME) ? request->username : pairfind(request->packet->vps, data->key_attr);
	if (key_vp == NULL){
		DEBUG("rlm_counter: Could not find the key-attribute in the request. Returning NOOP.");
		return RLM_MODULE_NOOP;
	}

	/*
	 *	Look for the attribute to use as a counter.
	 */
	count_vp = pairfind(request->packet->vps, data->count_attr);
	if (count_vp == NULL){
		DEBUG("rlm_counter: Could not find the count-attribute in the request.");
		return RLM_MODULE_NOOP;
	}

	key_datum.dptr = key_vp->strvalue;
	key_datum.dsize = key_vp->length;

	DEBUG("rlm_counter: Searching the database for key '%s'",key_vp->strvalue);
	pthread_mutex_lock(&data->mutex);
	count_datum = gdbm_fetch(data->gdbm, key_datum);
	pthread_mutex_unlock(&data->mutex);
	if (count_datum.dptr == NULL){
		DEBUG("rlm_counter: Could not find the requested key in the database.");
		counter.user_counter = 0;
		if (uniqueid_vp != NULL)
			strncpy(counter.uniqueid,uniqueid_vp->strvalue,UNIQUEID_MAX_LEN - 1);
		else
			memset((char *)counter.uniqueid,0,UNIQUEID_MAX_LEN);
	}
	else{
		DEBUG("rlm_counter: Key found.");
		memcpy(&counter, count_datum.dptr, sizeof(rad_counter));
		free(count_datum.dptr);
		if (counter.uniqueid)
			DEBUG("rlm_counter: Counter Unique ID = '%s'",counter.uniqueid);
		if (uniqueid_vp != NULL){
			if (counter.uniqueid != NULL &&
				strncmp(uniqueid_vp->strvalue,counter.uniqueid, UNIQUEID_MAX_LEN - 1) == 0){
				DEBUG("rlm_counter: Unique IDs for user match. Droping the request.");
				return RLM_MODULE_NOOP;
			}
			strncpy(counter.uniqueid,uniqueid_vp->strvalue,UNIQUEID_MAX_LEN - 1);
		}
		DEBUG("rlm_counter: User=%s, Counter=%d.",request->username->strvalue,counter.user_counter);
	}

	if (data->count_attr == PW_ACCT_SESSION_TIME) {
		/*
		 *	If session time < diff then the user got in after the
		 *	last reset. So add his session time, otherwise add the
		 *	diff.
		 *
		 *	That way if he logged in at 23:00 and we reset the
		 *	daily counter at 24:00 and he logged out at 01:00
		 *	then we will only count one hour (the one in the new
		 *	day). That is the right thing
		 */
		diff = request->timestamp - data->last_reset;
		counter.user_counter += (count_vp->lvalue < diff) ? count_vp->lvalue : diff;

	} else if (count_vp->type == PW_TYPE_INTEGER) {
		/*
		 *	Integers get counted, without worrying about
		 *	reset dates.
		 */
		counter.user_counter += count_vp->lvalue;

	} else {
		/*
		 *	The attribute is NOT an integer, just count once
		 *	more that we've seen it.
		 */
		counter.user_counter++;
	}

	DEBUG("rlm_counter: User=%s, New Counter=%d.",request->username->strvalue,counter.user_counter);
	count_datum.dptr = (char *) &counter;
	count_datum.dsize = sizeof(rad_counter);

	DEBUG("rlm_counter: Storing new value in database.");
	pthread_mutex_lock(&data->mutex);
	rcode = gdbm_store(data->gdbm, key_datum, count_datum, GDBM_REPLACE);
	pthread_mutex_unlock(&data->mutex);
	if (rcode < 0) {
		radlog(L_ERR, "rlm_counter: Failed storing data to %s: %s",
				data->filename, gdbm_strerror(gdbm_errno));
		return RLM_MODULE_FAIL;
	}
	DEBUG("rlm_counter: New value stored successfully.");

	return RLM_MODULE_OK;
}

/*
 *	Find the named user in this modules database.  Create the set
 *	of attribute-value pairs to check and reply with for this user
 *	from the database. The authentication code only needs to check
 *	the password, the rest is done here.
 */
static int counter_authorize(void *instance, REQUEST *request)
{
	rlm_counter_t *data = (rlm_counter_t *) instance;
	int ret=RLM_MODULE_NOOP;
	datum key_datum;
	datum count_datum;
	rad_counter counter;
	int res=0;
	VALUE_PAIR *key_vp, *check_vp;
	VALUE_PAIR *reply_item;
	char msg[128];

	/* quiet the compiler */
	instance = instance;
	request = request;

	/*
	 *	Before doing anything else, see if we have to reset
	 *	the counters.
	 */
	if (data->reset_time && (data->reset_time <= request->timestamp)) {
		int ret2;

		data->last_reset = data->reset_time;
		find_next_reset(data,request->timestamp);
		pthread_mutex_lock(&data->mutex);
		ret2 = reset_db(data);
		pthread_mutex_unlock(&data->mutex);
		if (ret2 != RLM_MODULE_OK)
			return ret2;
	}


	/*
	 *      Look for the key.  User-Name is special.  It means
	 *      The REAL username, after stripping.
	 */
	DEBUG2("rlm_counter: Entering module authorize code");
	key_vp = (data->key_attr == PW_USER_NAME) ? request->username : pairfind(request->packet->vps, data->key_attr);
	if (key_vp == NULL) {
		DEBUG2("rlm_counter: Could not find Key value pair");
		return ret;
	}

	/*
	 *      Look for the check item
	 */
	if ((check_vp= pairfind(request->config_items, data->check_attr)) == NULL) {
		DEBUG2("rlm_counter: Could not find Check item value pair");
		return ret;
	}

	key_datum.dptr = key_vp->strvalue;
	key_datum.dsize = key_vp->length;


	/*
	 * Init to be sure
	 */

	counter.user_counter = 0;

	DEBUG("rlm_counter: Searching the database for key '%s'",key_vp->strvalue);
	pthread_mutex_lock(&data->mutex);
	count_datum = gdbm_fetch(data->gdbm, key_datum);
	pthread_mutex_unlock(&data->mutex);
	if (count_datum.dptr != NULL){
		DEBUG("rlm_counter: Key Found.");
		memcpy(&counter, count_datum.dptr, sizeof(rad_counter));
		free(count_datum.dptr);
	}
	else
		DEBUG("rlm_counter: Could not find the requested key in the database.");

	/*
	 * Check if check item > counter
	 */
	DEBUG("rlm_counter: Check item = %d, Count = %d",check_vp->lvalue,counter.user_counter);
	res=check_vp->lvalue - counter.user_counter;
	if (res > 0) {
		DEBUG("rlm_counter: res is greater than zero");
		if (data->count_attr == PW_ACCT_SESSION_TIME) {
			/*
			 * Do the following only if the count attribute is
			 * AcctSessionTime
			 */

			/*
		 	*	We are assuming that simultaneous-use=1. But
		 	*	even if that does not happen then our user
		 	*	could login at max for 2*max-usage-time Is
		 	*	that acceptable?
		 	*/

			/*
		 	*	User is allowed, but set Session-Timeout.
		 	*	Stolen from main/auth.c
		 	*/

			/*
		 	*	If we are near a reset then add the next
		 	*	limit, so that the user will not need to
		 	*	login again
		 	*/
			if (data->reset_time && (
				res >= (data->reset_time - request->timestamp))) {
				res += check_vp->lvalue;
			}

			if ((reply_item = pairfind(request->reply->vps, PW_SESSION_TIMEOUT)) != NULL) {
				if (reply_item->lvalue > res)
					reply_item->lvalue = res;
			} else {
				if ((reply_item = paircreate(PW_SESSION_TIMEOUT, PW_TYPE_INTEGER)) == NULL) {
					radlog(L_ERR|L_CONS, "no memory");
					return RLM_MODULE_NOOP;
				}
				reply_item->lvalue = res;
				pairadd(&request->reply->vps, reply_item);
			}
		}

		ret=RLM_MODULE_OK;

		DEBUG2("rlm_counter: (Check item - counter) is greater than zero");
		DEBUG2("rlm_counter: Authorized user %s, check_item=%d, counter=%d",
				key_vp->strvalue,check_vp->lvalue,counter.user_counter);
		DEBUG2("rlm_counter: Sent Reply-Item for user %s, Type=Session-Timeout, value=%d",
				key_vp->strvalue,res);
	}
	else{
		char module_fmsg[MAX_STRING_LEN];
		VALUE_PAIR *module_fmsg_vp;

		/*
		 * User is denied access, send back a reply message
		*/
		sprintf(msg, "Your maximum %s usage time has been reached", data->reset);
		reply_item=pairmake("Reply-Message", msg, T_OP_EQ);
		pairadd(&request->reply->vps, reply_item);

		snprintf(module_fmsg,sizeof(module_fmsg), "rlm_counter: Maximum %s usage time reached", data->reset);
		module_fmsg_vp = pairmake("Module-Failure-Message", module_fmsg, T_OP_EQ);
		pairadd(&request->packet->vps, module_fmsg_vp);

		ret=RLM_MODULE_REJECT;

		DEBUG2("rlm_counter: Rejected user %s, check_item=%d, counter=%d",
				key_vp->strvalue,check_vp->lvalue,counter.user_counter);
	}

	return ret;
}

static int counter_detach(void *instance)
{
	rlm_counter_t *data = (rlm_counter_t *) instance;

	paircompare_unregister(data->dict_attr, counter_cmp);
	if (data->gdbm)
		gdbm_close(data->gdbm);
	free(data->filename);
	free(data->reset);
	free(data->key_name);
	free(data->count_attribute);
	free(data->counter_name);
	free(data->check_name);
	free(data->service_type);
	pthread_mutex_destroy(&data->mutex);

	free(instance);
	return 0;
}

/*
 *	The module name should be the only globally exported symbol.
 *	That is, everything else should be 'static'.
 *
 *	If the module needs to temporarily modify it's instantiation
 *	data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
 *	The server will then take care of ensuring that the module
 *	is single-threaded.
 */
module_t rlm_counter = {
	"Counter",
	RLM_TYPE_THREAD_SAFE,		/* type */
	NULL,				/* initialization */
	counter_instantiate,		/* instantiation */
	{
		NULL,			/* authentication */
		counter_authorize, 	/* authorization */
		NULL,			/* preaccounting */
		counter_accounting,	/* accounting */
		NULL,			/* checksimul */
		NULL,			/* pre-proxy */
		NULL,			/* post-proxy */
		NULL			/* post-auth */
	},
	counter_detach,			/* detach */
	NULL,				/* destroy */
};